Packets or articles are generally mounted on pallets by means of a packaging band, in order to ensure that these packets and articles are transported safely and without being damaged.
In addition to steel bands, plastic bands, predominantly composed of polyester or polypropylene, are also being increasingly used for this purpose. Once the packaging band has been passed around the pallet and the packaged item, the packaging band is tensioned and closed by means of a closure device, for example an electrical hand-held appliance. The power supply for the closure device may be provided both via the mains system and via a rechargeable battery. The closure device may in this case, for example, be a welding appliance with a rechargeable battery.
The closure device is moved onto the band to be closed by the operator, by hand. This has the disadvantage that the closure device is relatively heavy, generally being 2.5 to 6 kilograms. The further exacerbating factor is that the closure device must be held with one hand, since the packaging band must be threaded in using the other hand. This leads to correspondingly high physical stress on the operator.
Once the packaging band has been threaded in, the packing band is tensioned by the closure device, which is generally also in the form of a tensioning device. The parts of the packaging band which are located on top of one another are then welded, and the excess packaging band is cut off. The cut-off end of the packaging band can be rolled up again onto the strapping device, and now represents the start of the packaging band for strapping a further pallet or a further article.
In one simple embodiment, the strapping device may simply be a band unrolling device or a holder for a packaging band roll. In one advantageous embodiment, a design of the strapping device according to the packaging apparatus which is described in DE 199 16 193 C2 and which can be used in a mobile manner is possible.
A further strapping device is disclosed, for example, in DE 298 08 111 U1.
The handling of the closure device is particularly disadvantageous for the operator when the pallet to be closed or the article to be closed is higher than the chest level of the operator since, in this case, the closure device can no longer be placed on the top face of the packaged item, in the normal way. As soon as the pallet to be closed or the article to be closed is higher than the chest level of the operator, the operator has to tension, close and cut off the packaging band in the vertical plane. Owing to the physical state of health, some people cannot carry out this activity. The method, which is otherwise well proven, for packaging pallets and articles by means of a transportable apparatus, in particular according to DE 199 16 193 C2, can thus not be used in some cases.
The disadvantages which result from the use of the closure device in this case apply both to strapping devices which can be used in a mobile manner and to stationary strapping devices.
Even if the pallet or the article is not higher than the chest level of the operator, this does not save the operator having to apply force since, in this case, the closure device must be placed on the top face of the packaged item.
A further disadvantage of the closure device is that, as has been found in practice, these devices often fall down, thus resulting in a considerable risk of injury and, furthermore, the appliances are often damaged.
Holders, so-called balancers, are known from the prior art which are attached to the ceiling and to which the closure devices can be attached by means of a spring cable run. The spring cable run compensates for the weight of the attached closure device, so that it can be used more easily. The balancers have a cable which is wound up on a spool that is supported by a spiral spring.
However, balancers have the disadvantage that they are attached to a girder or to the ceiling in a stationary manner. Mobile use of the transportable apparatuses for strapping and/or bundling pallets or articles is thus not possible. Furthermore, in order to ensure easy accessibility, the closure devices are generally hung at the operator's head height, resulting in a considerable risk of injury.
The main advantages of the mobile apparatus for strapping and/or bundling pallets in contrast to a stationary apparatus, namely the mobility and the independence from a mains connection, are lost by balancers that are mounted in a stationary manner.